The invention relates to multi-channel communication systems, including active acoustic attenuation systems, and vehicle applications.
The invention arose during continuing development efforts relating to the subject matter of U.S. Pat. Nos. 4,677,676, 5,033,082, 5,216,721 and 5,216,722, all incorporated herein by reference. The invention involves an intercom communication system in a multi-channel application having one or more zones subject to noise from one or more noise sources, and one or more speaking locations in each zone.
One exemplary application of the invention is in an automobile where the front seat is a first zone and the rear seat is a second zone, and the left front passenger is in a first speaking location, the right front passenger is in a second speaking location, the left rear passenger is in a third speaking location, and the right rear passenger is in a fourth speaking location. Engine noise, road noise, etc. is canceled at each location, including cross-coupled noise between channels, but not speech from another location.
The invention has numerous other applications where communication is desired in multi-channel noisy environments.